Topic on VisualEditor/Feedback

It would be great if the editor could detect, when I am about to add a duplicate citation.

I just tested it this way and it showed me no warning:

1. Add an URL via automatic tool (tab) there.
2. Go somewhere else and add another URL, paste exactly the same URL as before.
3. And it created exactly the same text and did not notify me, one was there already.

I think checking whether one is about to re-add exactly the same URL would be an easy check, you can add.

Does this sound like phab:T126488 to you?

Yes, exactly!